Github user spmallette commented on a diff in the pull request:
https://github.com/apache/tinkerpop/pull/876#discussion_r202446882
--- Diff:
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/traverser/B_LP_NL_O_P_S_SE_SL_Traverser.java
---
@@ -0,0 +1,156 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.tinkerpop.gremlin.process.traversal.traverser;
+
+import org.apache.commons.collections.map.ReferenceMap;
+import org.apache.tinkerpop.gremlin.process.traversal.Step;
+import
org.apache.tinkerpop.gremlin.process.traversal.traverser.util.LabelledCounter;
+
+
+import java.util.Iterator;
+import java.util.Stack;
+
+public class B_LP_NL_O_P_S_SE_SL_Traverser<T> extends
B_LP_O_P_S_SE_SL_Traverser<T> {
+
+ protected Stack<LabelledCounter> nestedLoops;
+ protected ReferenceMap loopNames = null;
--- End diff --
Could you explain a bit further why a weak reference is desirable here? You
mentioned that it helps simplify `resetLoops()` but I'm unfortunately not
making the connection as to why even with the phraseology you followed with
about not needing "to walk the Map or store the 'loop name' multiple times."
---
